Instinctive wringer release



Jan. 3, 1967 v. w. cUTHBE-:RT ETAL 3,295,341

INSTINCTIVE WRINGER RELEASE I N VENTO/.

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INSTINCTIVE WRINGER RELEASE FiledMarch 12, 1965 5 Sheets-Sheet 5 I NVENTOR.

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INSTINCTIVE WRINGER RELEASE 5 Sheets-Sheet i.

Filed March l2, 1965 Illrl mm @M @pie ATTORNEYS Jan- 3 1967 v. w. CUTHBERT ETAL 3,295,341

INSTINCTIVE WRINGER RELEASE Filed March l2, 1965 5 Sheets-Sheet 5 IN VENTOR ATTORNEYS [H M @QW/@1,

United States Patent Office 3,295,3il `Patented Jian. 3,1967

3,295,341 INSTINC'I'HVE WRENPGER RELEASE Victor W. Cuthbert, Sodus, and Robert A. Brenner, St. Joseph, Mich., assignors to Whirlpool Corporation, Benton Harbor, Mich., a corporation of Delaware Filed Mar. 12, 1965, Ser. No. 446,458 1l Claims. (Cl. eti-256) The instant application is a continuation-in-part of our pending application for patent entitled Instinctive Wringer Release, filed August 24, 1964,Serial No. 391,571, now abandoned. The instant application, however presents an added improved embodiment of themechanism for releasing pressure on the rolls.

This invention relates to improvements in an instinctive pressure release for wringers, and more particularly to pressure release mechanism for use with washing machine wringers embodying a pair of pressurized rolls through which clothing or other material is passed to expel moisture from the same, the mechanism operating upon an instinctive movement of the operator or other person inadvertently caught between the rolls to release the pressure on the rolls, the invention being highly desirable for use in connection with household washing machines and the like, although the invention will have other uses and purposes as will be apparent to one skilled in the art.

It has become desirable in connection with pressure roll I type Washing machine wringers to provide mechanism for automatically releasing pressure between the rolls upon an instinctive movement of a person having a hand or arm caught between those rolls. It is instinctive for the operator to endeavor to jerk her hand from between the rolls if it is caught, and such movement effects a pivoting of the wringer frame thus actuating the pressure release mechanism. It is also desirable to have such mechanism operated by a downward pivotal movement of the wringer frame in the event a child had its hand caught between the rolls and in panic merely dropped toward the oor, the weight of the child then pivoting the wringer frame and actuating the pressure release mechanism. With mechanism of this character, it is not necessary to strike, push or pull upon the customary pressure release bars provided on most commercial washing machine wringers. An instinctive reaction sufficiently violent to move the wringer frame is all that is necessary.

In instinctive pressure release mechanism, it is important that the mechanism be so constructed that during normal usage of the wringer the pressure is not unexpectedly and unintentionally released by the mechanism responding to normal vibration and slight pressure on the wringer frame. It is also highly desirable that the mechanism be responsive to an amount of force on the wringer head that is uniform during all operations. It is also highly desirable to eliminate any play between connected portions ofthe mechanism that might tend to vary the amount of pressure on the wringer necessary to actuate the mechanism.

While attempts have been made in the past to provide instinctive pressure release means for wringers, such attempts have in the main been futile in providing a commercially satisfactory structure. These former attempts have frequently resulted in complicated mechanism that was prone to act upon slight movement of the wringer frame during normal usage and thus release pressure unexpectedly and unintentionally. In other instances, no provision was made for a downward pivoting of the frame which, of course, in the case of children is highly irnportant. Inother instances, the rotation of the wringer rolls was not stopped at the same time pressure between the rolls was released.

VWith the foregoing in mind, it is an important object of the instant invention to provide roll pressure release mechanism for wringers which is simple in construction and requires a predetermined amount of force to pivot the wringer frame and actuate the release means, whereby the release mechanism is not triggered accidentally and unintentionally during normal usage of the wringer in response to vibrations, variances in amount of material passed between the rolls, light touches against the wringer frame, and the like.

Another object of the invention is to provide an improved instinctive pressure release mechanism for wringers that functions to release pressure between the rolls upon movement of the frame in either direction laterally as well as in a downward vertical direction.

It is also an important feature of this invention to provide instinctive roll pressure release means for wringers which when actuated not only effects release of pressure between the rolls but also declutches the drive to the rolls and stops rotation of the rolls.

Another important object of the instant invention is to provide instinctive pressure release mechanism for wringers so constructed as to be responsive to the same amount of push or pull force at every operation to actuate the mechanism.

It is also an important feature of this invention to provide instinctive release mechanism for wringers wherein the parts are so connected that any play between them is innocuous insofar as it might cause any variation in the amount of force required to actuate the mechanism.

Still another feature of this invention is the provision of instinctive pressure release mechanism for wringers that is automatically latched in operative position when pressure is applied to the wringer rolls.

A further desideratum of this invention is the provision of instinctive roll pressure release means that are simple in construction, economical to install, positive in action, and highly durable.

While some of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosures, taken in conjunction with the accompanying drawings, in which:

FIGURE l is a fragmentary elevational view of a roll `type wringer provided with instinctive roll pressure release mechanism embodying principles of the instant invention; FIGURE 2 is a fragmentary bottom plan view of the structure of FIGURE l;

FIGURE 3 is a fragmentary elevational view showing the instinctive release mechanism mounted between the wringer frame and wringer head, and indicating operation of the same in dotted lines;

FIGURE 4 is a fragmentary top plan view of the structure of FIGURE `3;

FIGURE 5 is a fragmentary side elevational view illustrating another embodiment of instinctive roll pressure release mechanism embodying principles of the instant invention;

. FIGURE 6 `is a fragmentary top plan View of the structure of FIGURE 5;

FIGURE 7 is` a fragmentary bottom plan viewV ofthe structure of FIGURE 5; and

`FIGURE 8 is a fragmentary elevational view of the latching means.

As shown on the drawings:

Both illustrated embodiments of the instant invention are shown in association with a wringer which may be of a conventional typeso the detailed structure thereof need not be specifically described herein. A general description of thecomponent working parts will be suicient.

The wringer in general includes a frame 1 having outboard and inboard end stiles 2 and 3 respectively upstanding therefrom. Within the frame upper and lower wringer rolls 4 and 5 are mounted in a known manner, the lower roll 5 being driven by way of a wringer gear 6. FIGURE 3, which meshes with forward and reverse drive gears 7 and 8 respectively either of which is individually driven by a drive clutch 9, such gearing being contained in a wringer head 10.

Pressure is applied to the rolls by a pair of like spring cages 11-11, slidable in the end stiles 2 and 3 of the frame. Each spring cage has a lug 12 extending through a suitable slot on each side of the respective end stile. The construction and operation of the spring cages 11-11 are more fully set forth and described in George D. Conlee U.S. Letters Patent No. 3,216,228 issued November 9, 1965.

Actuation of the springs to apply pressure is by means of a suitable toggle linkage disposed substantially in a horizontal plane under the frame of the wringer, this toggle linkage being shown in FIGURE 2 in pressure applying position. The toggle linkage comprises a at plate-like lever 13 of irregular shape which pivots around a drain neck 14 for the wringer. A substantially L-shaped link 15 is pivoted to an intermediate portion of the lever 13 as indicated at 16, and the other end of this link is pivoted at 17 to an upstanding U-shaped lever 18 pivoted in its upper portion, FIGURE 1, to the frame by a crosspin 19. Another L-shaped lever 20 disposed in opposed position to the lever 15 is pivoted to the plate 13 at 21, a point substantially opposite to the pivot connection 16. This lever is also pivoted at 22 to a U-shaped link or lever 23 of the same construction as the lever 18.

Each of the U-shaped levers has an ear 24 extending outwardly from each side thereof over the lugs 12 on the respective spring cage. As the toggle linkage is moved to the position seen in FIGURE 2 by a horizontal pull, on a rod 25, the at lever 13 turns counterclockwise as seen in FIGURE 2, drawing in the levers 15 and 20 and causing the U-shaped levers 18 and 23 to pivot around their respective points causing the upper ends of these levers to move downwardly and the ears 24 to engage the lugs 12 to force the spring cages down and apply pressure to the rolls. The pressure is maintained on the rolls by virtue of the overcenter position of the toggle linkage, the pivot points 16 and 21 being on opposite sides of an imaginary line passing through the centers of the pivot points 17 and 22. In order to release the pressure it is only necessary to move the toggle mechanism slightly from the overcenter position. If desired, pivotal pressure release bars of a known type, fragmentarily indicated at 26, may be provided, these bars having means to engage the toggle mechanism and move it to free position.

Attached to the U-shaped lever 18 on both sides of stile 3 are a pair of arms 27, only one of which is shown, which extend outwardly toward the wringer head and underlie an ear 28 which extends from clutch lever 28a. Lever 28a is shown in its neutral position in FIGURE 3 to more clearly show ear 28. When lever 28a is moved to its forward or reverse position, ear 28 moves with lever 28a to engage a finger 27a (FIGURE 4) on arm 27, and drive clutch 9 engages one of the gears 7 or 8. When the pressure release mechanism is actuated, U-shaped lever 18 is rotated counterclockwise about pivot 19, and in turn rotates arms 27 in a counterclockwise or upward direction as seen in FIGURE 3. The upward moving arm 27 engages ear 28 and throws lever 28a into the neutral position shown in FIGURE 3, which disengages drive clutch 9.

The instinctive release mechanism illustrated in FIG- URES 1 through 4 includes a bracket 29 welded to the end stile 3 of the frame. This bracket has a top flange 30 extending outwardly over the top of the wringer head 10 and substantially at the midpoint thereof the flange 30 carries an upstanding headed pin 31. As seen best in FIGURES 2 and 3 the bracket 29 has a lower flange 32 extending outwardly beneath the adjacent part of the wringer head, which flange is apertured for loose engagement as indicated at 33 around the shank of a headed pin 34 carried by and depending from the lower part of the wringer head 10.

As seen best in FIGURE 4, a at bar 35 is centrally pivoted to the aforesaid pin 31 upstanding from the top bracket flange 30. The bar 35 has a reduced end portion 36 which remains in abutment with a stop plug 37 upstanding from the wringer head 10. This stop plug 37 prevents the bar from ever pivoting in a counterclockwise direction as viewed in FIGURE 4. The opposite reduced end portion 38 of the bar is normally in contact with the upper end 40 of a vertical lever 41 having a notch 42 in its upper end to receive the end of the bar as seen in FIGURE l. This vertically disposed lever 41 is pivoted near its upper end to a pin 43 projecting from the wringer head 10.

A horizontally disposed rod 44 has one end thereof connected to the lower end of the lever 41 as indicated at 45, and the other end of this rod as seen best in FIG- URE 2 extends through an elongated generally horizontal slot in a lug 46 depending from the aforesaid plate lever 13 of the toggle linkage. The lug is mounted for rotation relatively to the lever 13, if deemed necessary. The rod 44 carries a washer or the equivalent 44a on the end portion thereof extending through the lug 46. Consequently, as the lever 41 is pivoted from its normally vertical position toward the dotted line position of FIG- URE 3, the rod 44 by virtue of its pull on an outside location of `the at lever 13 forces the toggle mechanism out of its overcenter position and releases pressure upon the wringer rolls. The lever 41 is only pivoted out of its vertical position by pressure thereon of the end 38 of the bar 35, and such pressure can only be established by pivotal movement of the bar which results from a pivotal movement of the wringer frame relatively to the wringer head. In order to prevent accidental or unintentional pressure release, it is desirable to establish a predetermined force tending to maintain the wringer frame in alignment with the wringer head as seen in FIGURE 4, which force must be overcome in order to pivot the wringer frame relatively -to the head and cause pressure release. To this end, we have provided a spring 47, seen in FIGURE 3, with one end anchored to the wringer frame and the other end anchored to the lower portion of the lever 41. The spring may be tensioned to an amount in the neighborhood of 20 pounds which force must be overcome before the lever 41 can be pivoted to pressure release position.

In operation, the instant instinctive release mechanism is simple and positive. If a force exceeding that of the spring 47 is applied against the wringer in either direction horizontally, the wringer frame will pivot about the junction line 48 between the bracket 29 and the wringer head, or about the junction line 49 between the bracket and head depending upon the direction of pull or push. Such pivoting movement of the wringer relatively to the head will move the pin 31 to the left as seen in FIGURE 4, and since the end 36 of the bar 35 is held against movement by the stop lug 37, the bar must pivot clockwise as seen in FIGURE 4 and pivot the lever 41 towards the dotted line position of FIGURE 3, thereby releasing roll pressure. The wringer frame may also be pivoted downwardly relatively to the head by virtue of the loose connection 33 between the bottom bracket flange and the pin 34 and also by virtue of a slight clearance 50 between the lower part of the wringer head and the bracket 29. In that event, the pin 31 will again be pulled to the left as seen in FIGURE 4 causing the bar 35 to actuate the lever 41, and pressure is promptly released. Only a relatively slight pivotal movement *of the wringer frame relatively to the head is necessary because of the high pivot point 43 for the lever J 4l, the bottom end of the lever moving a comparatively great distance upon a relatively slight opposite movement of the upper end of the lever. Whenever pressure is released by virtue of pivoting the wringer frame, the driven roll is declutched from the driving mechanism causing roll rotation to also cease simultaneously with pressure release, as above explained.

The embodiment of the invention illustrated in FIG- URES 5 through 8 includes the same bracket 29 with top and bottom flanges 30 and 32 connected in the same way with the wringer head l and the at bar 35, as above described. In thisiinstance, however, the reduced end 33 of the bar 35 is normally in contact with a reduced end portion Slt on the short leg of a substantially L-shaped lever 52, the longer leg of which is disposed substantially horizontally as best seen in FGURE 5, and the lever has an offset portion S3 in an intermediate part thereof so the opposite end of the lever is farther away from the wringer head l0 than the end portion 5l. Substantially at the angle between the legs thereof, the lever 52 is pivotally mounted about a pin 54 projecting outwardly from the wringer head and xed thereto. The outer `free end of the lever 52 is connected at 55 with the end of a tension spring 56 the other end of which is connected to a stirrup 57 xed to a nut 53 threadedly engaged with the shank of a headed adjusting bolt 59. The bolt extends through one flange of an angle bracket 6i) bolted or equivalently secured to the side face of the wringer head l0, This spring pulling downwardly on the lever 52 causes the reduced end 5l to bear against the end 38 of the bar 3S and the spring thereby tends to maintain the wringer in alignment with the wringer head to prevent accidental or unintentional pivotal movement of the wringer relatively to the wringer head. This spring may be tensioned to an amount in the neighborhood of 20 pounds, which force must be` overcome before the wringer can be pivoted suiciently relaitvely to the head to actuate the release mechanism.

The pressure holding toggle linkage of the wringer is released by means of an operating member which may be in the form of a rod 6l having one end engaged within a slot 62 in the pivotal lever 52, and the other end engaged as at 63 in one eind of a sere slide 64. The slide 64 is reciprocal through slots in the walls 65-65 of a U-shaped bracket 66 bolted to the wringer head as indicated at 67. The slot in the left hand wall 65 FIGURE 5, may be a trifle longer than the width of the slide 64, and the slot 68 in the right hand wall 65 FIGURE 5, is of suilicient length to permit the passage of a sere 69 on the slide through the slot, as seen best in FIGURE 8. This slide 64 is urged outwardly toward the wringer head constantly by a compression spring 'i0 having one end bearing against the left hand wall 65 FIGURE 5, of the bracket and the `other end bearing against a washer "7l or the like pinned to the slide as indicated at 72. The inner end of the slide is connected as indicated at 73 to the aforesaid rod 44 which moves the toggle linkage of the wringer out of overcenter position to release pressure on the rolls. The spring 7) is of sufcient strength to exert a pull on the nod 44 strong enough to move the toggle linkage.

The operation of this embodiment of the invention is also extremely simple and positive in action. As previously described the relief Si) in the wringer head permits a downward pivotal movement of the wringer frame. The wringer may also be pivoted laterally relatively to the head about either junction line fla-8 or 49.

It is clear from the foregoing that there will be negligible play between the connections of the spring 56 and between the connections at each end of the pull member 6l. Accordingly, the force necessary to pivot the wringer will be uniform or the same every time. Movement in any of these directions must be sufliciently strong to overcome the spring 56 so the pressure on the wringer rolls will not be inadvertently, accidentally, or unintentionally released.

`and easily applied towringers already manufactured so vforce on rod 44, `sullcient to release the wringer toggle mechanism, and pressure on the rolls is immediately rei leased. When the wringer toggle mechanism is moved to overcenter position to reset pressure on the rolls, the slide 6d is retracted through the slots in the wall-.s of the bracket 66 by the rod 44 against the action of the spring 70 until `the serev 69 passes through the slot and drops in position to engage the adjacent wall below the slot and latch the relative parts against the action of the spring 70.

The pressure or force necessary to pivot the wringer to cause a release of pressure by an instinctive movement may be varied by adjustinging the bolt 59 to put more or less tension on the spring 56.

From the foregoing, it is apparent that we have provided'isimple, economical, and highly durable instinctive release mechanism for roll type wringers. The mechanism requires little if any servicing and may be simply that there is none but a negligible change in present tooling to provide the instinctive release.

It-will be understood that modication and variations may be effected without departing from the scope of the novel concepts of the present invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are dened as follows:

l. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

over-center toggle means to apply and maintain pressure on said rolls,

a wringer head,

a bracket rigidly connected to one end of said frame and pivoted in face-to-face relationship directly to said `head in a manner permitting movement of the frame relatively to said head in both vertical and horizontal planes about junction lines between the bracket and head,

a member on said head movable away from said wringer by action of said pivot means, and

a tension element` connecting said member to said toggle means to pull the same to released position.

2. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

over-center toggle means to apply and maintainf pressure on said rolls,

a wringer head,

a bracket rigidly secured to one end of said frame and pivoted in face-to-face relationshipdirectly to -said head in a manner permitting movement of the frame relatively to said head in both vertical and horizontal planes `about junction linesbetween the bracket and head,

a member on said head movable away from said wringer by action ofisaid pivot means,

a tension element connecting said member to said toggle means to pullthe same to released position, and

spring means of predetermined strength. positioned to hold said member against movement.

3. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

means t-o apply and maintain pressure on said rolls,

a wringer head,

a bracket having horizontal flanges extending over -and under said head,

a pin depending from said head and having a loose lit with the lower of said flanges to permit movement of the frame relatively to said head in both vertical and horizontal planes,

a connection between said head and said pressure applying means to move the latter t-o released position upon pivotal movement of said frame relatively to said head, and

yieldable means of predetermined force tending to maintain said frame and head in alignment,

4. In a wringer having instinctive pressure release means,

a frame,

compression rolls in said frame,

releasable means to apply and hold pressure on said rolls,

a wringer head,

a bracket having horizontal flanges extending over and under said head secured t-o one end of said frame,

a pin depending from said head having a loose t with the lower of said anges,

a pin upstanding centrally from the upper of said flanges,

a bar centrally pivoted to said upstanding pin and movable when said frame is pivoted relatively to said head, and

means connected to said roll pressure applying means to release the same when activated by movement of said bar.

5. In a wringer having instinctive pressure release means,

a frame,

compression rolls in said frame,

releasable means to apply and hold pressure on said rolls,

a wringer head,

a bracket having horizontal anges extending over and under said head secured to one end of said frame,

a pin depending from said head having a loose fit with the lower of said anges,

a pin upstanding centrally from the upper ot said flanges,

a bar centrally pivoted to said upstanding pin,

a stop lug bearing against one end of said bar,

a lever pivoted to said head with one end abutted by said bar, and

a rod connected to the other end of said lever and to said pressure applying means to release the same when said lever is moved by said bar.

6. In a wringer having instinctive pressure release means,

a frame,

compression rolls in said frame,

releasable means to apply and hold pressure on said rolls,

a wringer head,

a bracket having horizontal llanges extending over and under said head secured to one end of said frame,

a pin depending from said head having a loose t with the lower of said franges,

a pin upstanding centrally from the upper of said flanges,

a bar centrally pivoted to said upstanding pin,

a stop lug bearing against one end of said bar,

a lever pivoted adjacent its upper end to said head with its upper endabutted by said head,

means connected between the lower end of said lever and said pressure applying means to release the latter when said bar moves said lever, and

spring means of predetermined load tending to restrain said lever against movement.

7. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

means to apply and maintain pressure on said rolls,

a wringer head,

a bracket rigidly secured to one end of said frame and pivoted directly to said head in a manner permitting movement of the frame relatively to said head in both vertical and horizontal planes,

latch means tending to hold said frame in alignment with said head,

spring means urging said latch means away from latching position,

an elongated element connecting said latching means with said pressure applying means to move the latter to released position, and

a member movable by the action of said pivot means to release said latch means.

8. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

means to apply and maintain pressure on said rolls,

. a wringer head,

pivot means connecting one end of said frame with said head and permitting movement of the frame relatively to said head in both vertical and horizontal planes,

latch means tending to hold said frame in alignment with said head,

spring means urging said latch means away from latching position,

an elongated element connecting said latching means with said pressure applying means t-o move the latter to released position,

a member movable by the action of said pivot means to release said latch means, and

spring means adjustable to a predetermined amount tending to hold said member against movement.

9. In a wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

means to apply and maintain pressure on said rolls,

a wringer head,

pivot means connecting one end of said frame with said head and permitting movement of the frame relatively to said head in both vertical and horizontal planes,

an elongated element connected to said pressure maintaining means,

latching means connected to said element to hold the same in position with pressure maintained on said rolls,

compression spring means of suicient strength to move the pressure maintaining means to released position acting on said latching means,

an L-shaped lever pivoted to said head adjacent the angle of the lever,

means acting on the short arm of said lever to pivot the same in response to movement of the wringer relatively to the head, and

a tension member connecting the long arm of said lever with said latching means to release the latching means upon movement of said lever.

10. In a Wringer with instinctive pressure release means,

a frame,

a pair of rolls in said frame,

pressure applying means to apply and maintain pressure on said rolls until released,

a wringer head,

pivot means rigidly secured to lone end of said frame connecting said frame end directly to said wlinger head and permitting movement Of the frame relatively to said Wringer head in both vertical and horizontal planes,

lever means tending to hold said frame in alignment with said Wringer head,

spring means urging said lever means toward a position wherein said frame and said wringer head are in alignment, spring biased means connected between said pressure applying means and said wringer head for releasing said pressure applying means when actuated, actuating means for controlling said spring biased means, and operating means connecting said lever means and said actuating means for operating said actuating means, whereby when said frame is moved out of alignment with said wringer head, said lever means is eiective to operate said operating means to thereby actuate said spring biased means to release said pressure applying means.

1li. In a wringer with instinctive pressure release means, a frame, a pair of rolls in said frame, over-center toggle means to apply and maintain pressure on said rolls, a Wringer head, a bracket rigidly secured to one end of said frame and having horizontal flanges extending over and under said head,

a pin depending from said head and having a loose t with the lower of said anges to permit movement of the frame relatively to said head in both vertical and horizontal planes,

a member movable by a pivotal movement of said frame,

a tension element connecting said member with said toggle means to move the same to released position, and

spring means of predetermined strength positioned to hold said member against movement.

References Cited by the Examiner UNITED STATES PATENTS 2,216,392 10/1940 Kauffman 68-269 2,216,395 10/1940 Kauffman 68--263 X 2,216,396 10/ 1940 Kauffman 68-269 2,216,400 10/1940 Kauffman 68-263 2,729,963 1/ 1956 Gabrielson et al 68--249 3,216,228 11/1965 Conlee 68-256 LOUIS O. MAASSEL, Primary Examiner. 

11. IN A WRINGER WITH INSTINCTIVE PRESSURE RELEASE MEANS, A FRAME, A PAIR OF ROLLS IN SAID FRAME, OVER-CENTER TOGGLE MEANS TO APPLY AND MAINTAIN PRESSURE ON SAID ROLLS, A WRINGER HEAD, A BRACKET RIGIDLY SECURED TO ONE END OF SAID FRAME AND HAVING HORIZONTAL FLANGES EXTENDING OVER AND UNDER SAID HEAD, A PIN DEPENDING FROM SAID HEAD AND HAVING A LOOSE FIT WITH THE LOWER OF SAID FLANGES TO PERMIT MOVEMENT OF THE FRAME RELATIVELY TO SAID HEAD IN BOTH VERTICAL AND HORIZONTAL PLANES, A MEMBER MOVABLE BY A PIVOTAL MOVEMENT OF SAID FRAME, A TENSION ELEMENT CONNECTING SAID MEMBER WITH SAID TOGGLE MEANS TO MOVE THE SAME TO RELEASED POSITION, AND SPRING MEANS OF PREDETERMINED STRENGTH POSITIONED TO HOLD SAID MEMBER AGAINST MOVEMENT. 